不完全型雄激素不敏感综合征产前诊断研究

Genetic analysis and prenatal diagnosis in a family with partial androgen insensitivity syndrome

目的对不完全型雄激素不敏感综合征(Partial Androgen Insensitivity Syndrome,PAIS)一家系进行病例报道及遗传分析,并对高危胎儿进行产前诊断。方法分析患者雄激素受体(AR)基因序列及第一外显子内的CAG重复,结合核型及产前超声判断胎儿是否罹患PAIS。结果 2名患者AR基因编码区及侧翼序列未见异常,男性胎儿获得了与疾病相关的CAG重复次数,超声检查提示其外生殖器发育异常。结论本研究对一个PAIS家系进行了遗传分析,虽未能明确AR基因突变,但连锁分析及产前超声均提示男性胎儿罹患PAIS。本研究可为同样病例的遗传分析、产前诊断和遗传咨询提供借鉴资料。

Objective To detect AR gene mutation in 2 patients of a partial androgen insensitivity syndrome family and perform prenatal diagnosis for the high risk fetus. Methods Eight exons and at least 100bp flanking intrinsic sequence ofAR gene were screened by PCR and direct sequencing. CAG repeats in exonl ofAR gene was used as a STR marker in linkage analysis. The amniocentesis was performed for determination of genetic gender and linkage analysis. The Fetal genital anomalies were scanned by color Doppler ultrasound. Results No mutation was found in two patients＇ AR gene. Linkage analysis indicated that the 21 times of CAG repeats was related to the phenotype in this family. The male fetus inherited the 21 times repeat of CAG, and antenatal sonographic diagnosis showed its external genitals was abnormal （micropenis, perineoscrotal hypospadia）. Conclusion Male fetus was still diagnosed as PAIS based on the results of linkage analysis and sonographic diagnosis, although no specific mutations ofAR gene were detected in PAIS patients.